一种宽带恒定跨导轨对轨运算放大器的设计

介绍了一种具有轨对轨输入功能的CMOS输入级电路。该电路克服了一般运算放大器只能工作在一定共模输入范围的输入级的缺陷，在各种共模输入电平下有着几乎恒定的跨导，使频率补偿更容易实现，且由于其工作原理与MOS晶体管的C—V解析关系无关，对制造工艺依赖性小，适用于深亚微米工艺。在此基础上，设计出了一种宽带的运算放大器，该运算放大器具有轨对轨输入、输出能力，可以作为常用模拟电路的基本单元模块。它没有严格的共模输入限制，跨导和整体性能稳定，适于为更大规模的数字／模拟混合信号系统提供行为级模型。

A Broadband Constant-Transconductance Rail-to-Rail CMOS Op-Amp for Low-Voltage VLSI Systems

A rail-to-rail CMOS input stage is presented,whose transconductance is nearly independent of the common-mode (CM) level,making it easy to realize frequency compensation. Since its operation does not rely on analytical square law,it has less dependency on the process and is applicable for deep sub-micron technologies. A wide-band operational amplifier is designed based on this transconductance,which features rail-to-rail input as well. In the case of the input CM level,it can avoid rigorous control and lead output signal to a full swing across the power supply range. Due to its consistent performance,the circuit is ready to be described in behavioral language for simulation in large-scale digital/analog mixed signal systems.